The present invention relates to an improvement of a sealing structure of a joint for three members, at which three members butt against each other and a joint therefor has a shape of T.
Concerning the sealing structure of a joint for three members, JP-A-Hei 10-231935 discloses a sealing structure of a joint for three members, at which a cylinder block (second member) is jointed to a cylinder head (first member) in a motor and a timing cover (third member) is jointed to end surfaces of the first two members.
The sealing structure of a joint for three members is characterized in that liquid gasket product is put between the end surfaces of the first and second members and the third member, that a plate-shaped gasket is disposed between the first and the second members, and that the sealing property is improved by suppressing bulge-out of the liquid gasket product from a T-shaped joint portion of the three members owing to a protruding portion formed on an end surface of the gasket.
In the sealing structure of a joint for three members described above only the liquid gasket product serves as sealing material used on the third member side.
That is, it is assumed that seal outside of the T-shaped portion relies also on the liquid gasket.
For example, in case where an oil inlet and outlet section is in the joint portion of the third member, depending on the construction of the motor, since the liquid gasket is unsuitable for high pression seal (because of blow-off), it is necessary to dispose separately a rubber O-ring.
Further, although the liquid gasket is an excellent material for filling a gap having a not plain shape such as a T-shape, it has an inconvenience that utilization environments or conditions outside of the T-shaped portion are fairly restricted.
The present invention has been made in order to overcome the drawback of the sealing structure of a joint for three members disclosed in the publication and a main object thereof is to provide a sealing structure, which can be used for a joint for three members, without using any liquid gasket outside of the T-shaped portion.
In order to achieve the above object, the present invention is characterized in that in a sealing structure of a joint for three members, in which a second member and a third member are butted against a first member in common so that a joint portion has a T-shape, at least one plate-shaped gasket, in which rubber layers are formed on two surfaces of a metal plate, is disposed at least between surfaces to be jointed where the second and the third member are butted against the first member in common and an opening is formed in the plate-shaped gasket at a portion, which is opposite to a T-shaped portion, the opening being filled with a liquid gasket sealing the T-shaped portion.